Integrated electronic hydraulic brake system

Abstract

Disclosed is an integrated electronic hydraulic brake system including an actuator having a master cylinder and a pedal simulator, an electronic stability control (ESC), and a hydraulic power unit (HPU) which are configured as a single unit. The integrated electronic hydraulic brake system may include an integrated hydraulic control unit and a power source unit, wherein the power source unit is separately provided to isolate the operational noise, and the integrated hydraulic control unit and the power source unit are connected to each other via an external pipe.

What is claimed is: 
     
       1. An integrated electronic hydraulic brake system for a vehicle comprising:
 an integrated hydraulic control device comprising a master cylinder to generate hydraulic pressure based on pedal force of a brake pedal, a reservoir coupled to an upper portion of the master cylinder to store oil, two hydraulic circuits, each of the hydraulic circuits being connected to two different pairs of wheels of the vehicle, an accumulator to store a predetermined level of pressure, flow control valves and pressure reducing valves connected to the two hydraulic circuits to control pressure transmitted from the accumulator to wheel cylinders installed at the wheels, a balance valve to connect the two hydraulic circuits and control pressure difference between the two hydraulic circuits, a pedal simulator connected to the master cylinder to provide reaction force of the brake pedal, and a simulation valve to control connection between the master cylinder and the pedal simulator; and 
 a power source unit comprising a pump to suction oil from the reservoir and discharge the suctioned oil to the accumulator to generate pressure in the accumulator and a motor to drive the pump, wherein 
 the power source unit is configured as a separate unit to isolate noise generated from the power source unit, and the integrated hydraulic control device and the power source unit are connected to each other via an external pipe, 
 wherein the balance valve is provided on a path connecting a first inlet path provided between one of the hydraulic circuits and one of the flow control valves to a second inlet path provided between the remaining hydraulic circuit and the remaining flow control valve, 
 wherein the flow control valves are connected in parallel to the accumulator. 
 
     
     
       2. The integrated electronic hydraulic brake system according to  claim 1 , wherein the two hydraulic circuits include a first hydraulic circuit connected to a right front wheel and a left rear wheel, and a second hydraulic circuit connected to a left front wheel and a right rear wheel. 
     
     
       3. The integrated electronic hydraulic brake system according to  claim 1 , wherein the balance valve is a Normally Closed solenoid valve, the balance valve being closed in normal times and opened based on pressure information when the pressure difference occurs between the two hydraulic circuits. 
     
     
       4. The integrated electronic hydraulic brake system according to  claim 1 , wherein the accumulator and the pump are connected to each other via the external pipe, and the external pipe has a check valve installed therein to prevent backward flow of pressure of the accumulator. 
     
     
       5. The integrated electronic hydraulic brake system according to  claim 1 , further comprising a return channel, and wherein each of the hydraulic circuits comprises:
 a Normally Open solenoid valve disposed upstream of the wheel cylinders to control transmission of the hydraulic pressure to the wheel cylinders; 
 a Normally Closed solenoid valve disposed downstream of the wheel cylinders to control discharge of the hydraulic pressure from the wheel cylinders; and 
 the return channel connects each of the Normally Closed solenoid valves to the reservoir. 
 
     
     
       6. The integrated electronic hydraulic brake system according to  claim 1 , wherein the integrated hydraulic control device further comprises first and second backup channels to connect the master cylinder to the two hydraulic circuits to control braking oil when the integrated electronic hydraulic brake system is abnormally operated, a first shut off valve to control connection between the first backup channel and the master cylinder, and a second shut off valve to control connection between the second backup channel and the master cylinder. 
     
     
       7. The integrated electronic hydraulic brake system according to  claim 6 , wherein the first and second shut off valves are Normally Open valves adapted to remain open in normal times and be closed during normal operation of braking. 
     
     
       8. The integrated electronic hydraulic brake system according to  claim 1 , wherein a simulation check valve is further provided in a channel connecting the master cylinder to the pedal simulator such that the pressure according to the pedal force of the brake pedal is transmitted to the pedal simulator only through the simulation valve. 
     
     
       9. The integrated electronic hydraulic brake system according to  claim 8 , wherein the simulation check valve is a pipe check valve having no spring to return the remaining pressure of the pedal simulator when the pedal force of the brake pedal is released. 
     
     
       10. The integrated electronic hydraulic brake system according to  claim 1 , wherein a plurality of pulsation attenuators are provided in channels connecting the flow control valves and pressure reducing valves with the two hydraulic circuits to minimize pressure pulsation. 
     
     
       11. The integrated electronic hydraulic brake system according to  claim 10 , wherein the flow control valves and the pressure reducing valves are Normally Closed valves adapted to remain closed in normal times.